So, quick technical note, but bounces don't hurt your damage at all. The frag still deals whatever damage it is supposed to do. It just loses less damage potential and changes direction.

Frag AP to 12 would be nuts. That's a 100% damage buff against anything ac6 or higher. For reference, my old mod that concentrated frags (20*250 instead of 50*100) and increased their AP just to 10 had them shredding ships.